Improvement in rivets and washers



anna seafa-r tau aan.

` Letters PatentNa. 97,866, datedillecember 14, 1869.

IMPROVEMENT IN RIVETS AND WASHEYRS.

yThe Schedule referredy to in thesev Letters Patent and making part of the same To all whom t may concern Be it known that I, EDWARD Bomann, of Pittsburg, in the county of Allegheny, and State of Pennsylvania, have inventedia new and useful Improvement in Rivets and Washers, us'ed for uniting the thin metallic sheets of steam-heated radiators; yandl hereby declare that the following is a lfull, clear, and exact description of myinvention, reference being had to the accompanying` drawings, forming part of this specicatiou, and-to the letters of reference marked thereon, in whichi t Figure l represents a longitudinal lvertieal section of two thin metallic -sheets united by my plan. Figure 2 represents a top viewof the same.l

Figure 3, an enlarged sectional view of the outside washer.

Figure 4, an enlarged sectional view of large'inside washer.'

Figure 5, enlarged viewr of thev rivet.

All the 4parts are lettered, and similar letters denote like partsin the several views.

' This invention is designed as au improvement upon that for which Letters Patent were granted to me the 9th day of February, 1869, numbered 86,7 26. In thatcase the'inside washer was made witlronly one end of its central hole concave, so that when used in connection with a conical-headed rivet, thatv portion of the sheetimmediately around the head ofthe rivet,

on closing it down,7 was drawn into the'concavity of the washer.

In this case I have made the central hole in the inside washer B concave at both ends, and use in connection therewith a convex washer, a, softhat the sheet N, farthest from the head of the rivet O, will` be drawn iuto'the concat-'ity of the washer B at that point, in thesame manner and to the same ext-ent as the head of the rivet G'draws the sheet P into-the vconcave portion of the inside washer B at its end, as

yaround both ends ofthe rivets is, iii/'this case, entirely overcome, owing -to the length of' bearing each sheet is given in the'central washers at its point of contact.

The curving of the sheets inward, at and around each end of the rivets, and the plan of drawing that portion into the concavities ofthe central washer, not

only prevents leakage, but tends to stiften ,both sheets and aid them in withstanding the outward pressure of steam.

l claim the combination of the rivet C, washers B and a, all constructed as described.

EDWARD BOURNE."

Witnesses Josua W. Enns, J. B. 'Wimmer'. 

